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Thread: How do we fill in an array using substring, FileReader and a txt file?

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    Question How do we fill in an array using substring, FileReader and a txt file?

    Got different types of information, which are evenly spaced apart.

    LUONGO ROBERT M 1,69 64,9 2343
    BUSH GEORGE M 1,47 52,2 1941
    GOLDBERG JOHN M 1,89 72,3 2101
    PAULSON MARTIN M 1,73 60,5 2232


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    Super Moderator Norm's Avatar
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    Default Re: How do we fill in an array using substring, FileReader and a txt file?

    Those lines that you have posted can be read into a String (for example with the Scanner class methods)
    Then what do you want done with the data?
    The String class's split method will separate a String at the spaces.

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    Default Re: How do we fill in an array using substring, FileReader and a txt file?

    Quote Originally Posted by Norm View Post
    Those lines that you have posted can be read into a String (for example with the Scanner class methods)
    Then what do you want done with the data?
    The String class's split method will separate a String at the spaces.
    What if there are several spaces between each type of information and there are numbers attached to the names?

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    Default Re: How do we fill in an array using substring, FileReader and a txt file?

    Quote Originally Posted by wholegrain View Post
    What if there are several spaces between each type of information and there are numbers attached to the names?
    Read the API docs for Scanner (and java.util.regex.Pattern and Matcher) - it can use regular expressions to cope with variable-sized inputs and delimiting space.

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    Default Re: How do we fill in an array using substring, FileReader and a txt file?

    I'd like to use substring since I already wrote a method to read lines and convert them into strings. Do I need to write a method in my class file? I have no idea how to do this exactly.

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    Super Moderator Norm's Avatar
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    Default Re: How do we fill in an array using substring, FileReader and a txt file?

    The Scanner class would be easier to use to get the words out of the String.
    To use the substring method, you would need to find the location of first byte and the location of last byte of each token and use their values in a substring method call. Finding the first non blank character after the end of a token will require a search loop to loop at each character in turn until you find a non blank. It can be tedious coding.

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